Can people who are naturally pessimistic, or even just prone to occasionally pessimistic thoughts, retrain their brains and become optimists?

Internationally known English psychologist Elaine Fox believes they can.

Her new book, "Rainy Brain, Sunny Brain: A Leading Psychologist Explains the New Science of Mind" promises to show people how to retrain their brains to overcome pessimism and achieve a more positive outlook.

Fox cites a variety of studies showing that optimists are not only happier, they generally are healthier, live longer and experience more success in life.

Those outcomes may be the result of optimists' beliefs they can cope with problems that come their way and take steps to solve challenges. Pessimists, on the other hand, are fearful of the future and feel that problems are beyond their control, according to Fox.

Unfortunately for pessimists, there are biological and psychological reasons why some people are more prone to negative or positive thinking.

Pessimists are drawn to negative information — even negative photos that flash on a screen so quickly most people do not consciously register their content. Optimists screen out the negative and focus on the positive.

A primitive part of our brains called the amygdala causes us to experience fear and alarm, while the intelligent prefrontal cortex helps us rationally think through threats. Activate the amygdala too often and the fear response grows stronger, weakening the prefrontal cortex's ability to dampen our fears. This response can happen to anyone, from a person with anxiety to a soldier suffering from post-traumatic stress disorder.

Pessimism and optimism may even have a genetic component. People with a certain type of transporter gene for serotonin — often known as the brain's "feel good" chemical — are drawn to negative images and their amygdala react more strongly when they see fearful faces.

All this seems very discouraging for people who would like to change their pessimistic views.

But Fox also describes promising new research showing that people can be shifted toward optimism. Our brains are surprisingly malleable, even during adulthood.

People can be trained in lab experiments to focus on positive rather than negative images.

Subjects who received this training reported less stress than control subjects when both groups were given a difficult test.

People with phobias can overcome their fears by being exposed to the trigger — such as a spider — over and over in a safe environment.

If you want to try some brain training yourself, Fox has a website where you can test whether you are an optimist or pessimist, then take part in an online game meant to shift you toward optimistic thinking.

I took the quick test to find out whether I was an optimist or pessimist and scored 47 points on a scale of negative 100 to positive 100 — putting me in the reasonably optimistic camp.

Then I played a game that required me to click on smiling faces as fast as I could while ignoring frowning faces. I got a startling result when I re-tested immediately after playing the game. My respectable score of 47 had shot up to a sky-high 92.

Fox's "Rainy Brain, Sunny Brain" website with information, tests and the positivity training game can be found at http://www.rainybrainsunnybrain.com/bbc-horizon/.

To go straight to a simplified version of the positivity training game, visit http://baldwinlab.mcgill.ca/labmaterials/materials_2fa.html.

Staff reporter Vickie Aldous can be reached at 541-479-8199 or vlaldous@yahoo.com. Follow her on Twitter at @VickieAldous.